1. Field of the Invention
The present invention relates to a high-frequency signal processing apparatus, and more particularly to an attachment structure for a combiner/distributor for use in a transmitter/receiver.
2. Description of the Related Art
Structures for positioning and fixing coaxial connectors to baseboards or casings are disclosed in Japanese Patent Laid-Open No. 2-103872, Japanese Utility Model Laid-Open Nos. 59-141678, 63-145280, 2-80968, and 3-53774. However, there is nothing disclosed in these Laid-Open documents with respect to an attachment structure according to the present invention for a combiner/distributor for use in a transmitter/receiver.
Japanese Patent Laid-Open No. 58-166802 reveals a filter device comprising a filter and a distributor disposed in the casing of the filter integrally with the input/output coupling loop of a resonator of the filter. While the distributor is attached to the filter in the disclosed filter device, the distributor has to be connected through a cable to terminals mounted on an attachment plate.
FIG. 1 of the accompanying drawings shows, in exploded perspective, another conventional attachment structure for a combiner/distributor.
As shown in FIG. 1, a plurality of connector housings 106 each with a plurality of coaxial connectors 107 disposed therein are fastened by a plurality of screws 109 to an attachment surface 103 of a back wiring board (BWB) 100, which serves as a baseboard. The back wiring board 100 has a plurality of arrays of connector insertion holes 102 defined therein at the same intervals as the coaxial connectors 107, the connector insertion holes 102 in each array being aligned with the longitudinal central axis of one of signal line connectors 101. The coaxial connectors 107 have connection terminals 108 projecting through the connector insertion holes 102 into the reverse side 104 of the back wiring board 100 which is opposite to the attachment surface 103. Connector cables 110 each having coaxial connection terminals 111a, 111b on both ends are connected at one end 112 to the connection terminals 108, and at the other end 113 to a combiner/distributor 105 which is spaced from the back wiring board 100.
Since the combiner/distributor 105 is spaced from the back wiring board 100, however, attachment fixtures (not shown) are required to secure the combiner/distributor 105 in position. Because connection cables 110 with coaxial connection terminals 111a, 111b are used, it is necessary to manufacture and adjust the connection cables 110, and, as a result, the cost of the entire assembly is high due to the required expenditure of material, machining, and manufacturing expenses.
The back wiring board 100 and the combiner/distributor 105 are generally accommodated in the transmitter/receiver. As the back wiring board 100 and the combiner/distributor 105 are positioned in different locations, a large installation space is required in the transmitter/receiver, which necessarily becomes large in size. The many spots that need to be connected make the assembling process inefficient and cause a high-frequency circuit on the baseboard to have reduced reliability.